The invention relates to a process and an apparatus for the manufacture of textured meat-like or fish-like products from protein-containing masses, preferably of comminuted muscle meat of marine or land animals, with an extensive similarity to the original muscle texture. The manufactured products have textural and sensory characteristics which make possible their use as partial or complete simulations of meat or fish products for industrial or culinary food preparations.
In the patent literature there are numerous methods proposed for the texturing of proteins, in which extrusion and spinning are the methods of choice for the formation of random or oriented textures. Recently, importance has been attributed to the freeze texturing of protein-rich vegetable or animal raw materials, especially from the point of view of the retexturing of comminuted muscle tissue. In such processes, the flaky textures that are formed are solidified in a subsequent step of the process; such variants are contained, for example, in DE-AS Nos. 2211944 and 2211943. Information is given on the practical performance of freeze-texturing in U.S. Pat. Nos. 4,084,017 and 4,167,550, and in DD Pat. No. 223355, but the processes referred to in the specifications evidently lack the necessary technical and technological reliability.
In order to achieve the formation of fibers in doughs of substances isolated from vegetable protein with a specific moisture content, it is proposed in DE-OS No. 2320782 and U.S. Pat. No. 3,973,044, and in Swiss Pat. No. 554140, to stretch the protein doughs with the formation of folds as the dough passes through two or more rolls revolving at specific speeds, followed by stripping them off. Subsequent manipulation to intensify the formation of fibers and to texturize by heating are said to result in fiber-like and hence meat-like products. Such processes are very expensive, since they require a dry, hydratable protein mixture on the basis of relatively costly substances isolated from proteins. Moreover, the products thus made generally have a boiled-meat character. The important disadvantage of the apparatus described for the practice of these processes consists in their exclusive limitation to stretching and folding. No technically practicable solutions are being offered for the further operations of fiber strengthening and texture fixation which are essential to these processes.